1. Field of the Invention
The present invention relates to a work vehicle that includes a tank that stores a liquid for purifying exhaust gas by reduction.
2. Description of Related Art
An exhaust device that purifies exhaust gas is mounted in a work vehicle such as a tractor in order to comply with regulations on exhaust gas emission of nitrogen oxides and the like, which have become more stringent in recent years. In this case, it is proposed that, in order to efficiently remove nitrogen oxides in exhaust gas by reduction, a reductant solution such as urea is injected into the exhaust gas. For this purpose, it is necessary to provide a tank storing such a reductant solution in a work vehicle.
In a work vehicle disclosed in Japanese Patent Laid-Open Publication No. 2013-151185, a urea water solution tank is mounted via brackets, mount brackets and the like to a cylinder block 7 of an engine and a transmission case, the urea water solution tank storing a urea water solution as a selective reduction nitrogen oxide catalyst to be sprayed into exhaust gas in order to remove nitrogen oxides in the exhaust gas. In this configuration, the urea water solution tank is arranged using a space between a vehicle body and the ground. Therefore, there is an advantage from a viewpoint of space utilization. However, the tank is exposed to hot air from the engine, and this is disadvantageous for the urea water solution that expands when heated. Further, when an amount of the urea water solution in the urea water solution tank is decreased, the urea water solution must be supplied. However, a supply structure of the urea water solution tank is not described in Japanese Patent Laid-Open Publication No. 2013-151185.
In a vehicle according to Japanese Patent Laid-Open Publication No. 2008-273372, a urea water solution inlet connecting to a urea tank and a fuel inlet connecting to a fuel tank are arranged close to each other and a common cap that covers both inlets is provided. The urea water solution is consumed at a slower rate as compared to the fuel. Therefore, rather than supplying the urea water solution alone, it is more likely that the urea water solution is also supplied when the fuel is supplied after having performed fuel supply several times. Therefore, that the urea water solution inlet and the fuel inlet connecting to the fuel tank are close to each other is advantageous to workability when supplying both the urea water solution and the fuel. However, measures are necessary to prevent one liquid (fuel or urea water solution) from being mistakenly supplied into the tank for the other liquid and to prevent one liquid from being scattered into the inlet for the other liquid when liquid supply is performed. Further, also in Japanese Patent Laid-Open Publication No. 2008-273372, the urea water solution tank, or at least a bottom surface of the urea water solution tank, is exposed to a space below a vehicle body, and no measures are taken against hot air from an engine.